How do remoras stick to their hosts?

BBC Wildlife contributor Stuart Blackman answers your wild question.


Remoras, also known as sharksuckers or suckerfish, are famous for their ability to hitch rides on larger fish and marine mammals by means of what looks like a suction cup on top of their heads. But suction is only part of the story.


The latest research shows that the cup, which is actually a modified dorsal fin, is lined with tiny barbs that create friction between the two surfaces. Large blood vessels running just under the organ also help by providing pressure against the host.

The result is that remoras are able to attach for long periods and release quickly without damaging either themselves or their host.

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Main image: Remoras and shark © iStock